1. Field of the Invention
This invention relates to a fastener for fastening together a plate-like base and a plate-like mounting piece of a component in an overlapped state, such as, for example, when securing a component to a car body. More specifically, the invention concerns a so-called one-way push type fastener which comprises a female body having a plurality of leg portions capable of being flared outwardly and a male body to be inserted into an insertion hole of the female body, and in which the male body is coupled to the female body by forcibly inserting it into the insertion hole of the female body, and wherein the male body can be further inserted so as to cause outward flaring of the leg portions of the female body so as to couple together a pair of overlapped plates between the flared leg portions and a head portion of the female body and then, wherein further, the male body can be inserted further into the female body so as to release the flaring of the leg portions of the female body and thereby permit unfastening of the plates.
2. Description of the Prior Art
A one-way push type fastener of the aforenoted type is disclosed in Japanese Patent Publication No. 48-13144. When fastening plates together with this fastener, it is necessary to insert the leg portions of the female body through aligned hole of the overlapped plates and, in this state, push in the male body. Therefore, when fastening a plate to the lower surface of a horizontally secured plate, it is necessary to hold the plate to be fastened at a fixed position so as to align the holes of the two plates, insert the fastener through the holes in this state and then push in the male body so as to effect fastening of the plates to each other.
Substantially the same operation is necessary in the case where a plate is fastened to a vertically secured plate. In either case, a plurality of operations are necessary.
In order to simplify the operation when fastening plates together, the practice has been to temporarily couple the female body, with which the male body has been temporarily coupled to the first plate, by passing the female body through a hole of the first plate and then inserting an end portion of the female body projecting from the hole of the plate into a hole of the other plate so that the holes of the two plates are penetrated by means of the female body. Subsequently, the male body is pushed into the female body so as to effect final fastening of the plates to each other.
This method involving the temporary coupling of the fastener body members has an advantage in that there is no need to support the female body so as to prevent the female body from being detached from the penetrated holes of the plates until the male body is pushed into the female body so as to effect the fastening of the plates together. This method, however, has a disadvantage in that the male body is in a state with its head projecting from the female body as to be liable to be erroneously pushed into the female body before effecting the fastening of the plates.
More particularly, when the fastener is in the temporarily coupled state, the leg portions can be readily moved to the flared state. Therefore, the male body can be pushed into the female body with a small force so as to cause flaring of the leg portions. In actual practice, the fastener cannot be inserted through the hole of the plate to be fastened to another plate, and this entails a rather cumbersome operation.